Prostate cancer is a relatively common type of cancer and the second leading cause of death in men. There are currently no reliable, non-invasive diagnostic tests available for prostate cancer and the only way to fully confirm the diagnosis of prostate cancer is a biopsy. A PSA (prostate specific antigen) test is the only available tumor marker, but PSA blood levels can be elevated for a number of reasons and do not necessary correlate with prostate cancer. Also, there are rare types of aggressive prostate cancers that cannot be diagnosed with the PSA test. This test for screening therefore has limitations and is still controversial.
Further, prostate-related PET tracers known in the art; e.g., mAb PET tracers, are associated with low clearance (high blood activity) due to prolonged biologic half life of the antibody. This generally leads to low tumor-to-muscle ratios.